The present invention relates to a device for preparing a paste for cosmetic use, particularly a paste for dying or bleaching hair, in a way that is sheltered from the air.
Such pastes are generally obtained by mixing, just before use, at least two components of which at least one is in the cream form and the other component or components is/are in the powder form or possibly a cream form with a third liquid component such as a solvent, in particular water, which may be added to the mix to adjust the degree of fluidity of the eventual paste.
Thus, in the preparation of hair dying or bleaching pastes to be applied with a brush, a dye powder or bleaching powder is mixed with an oxidizing cream and the paste formed after mixing is applied to the entire head of hair or applied in streaks for a specific length of time, after which the hair is rinsed with water and dried.
When a powder component is used, it is important to prevent the powder from being blown into a cloud, which is irritating for the nasal mucosa and gives off an unpleasant odor.
Thus, it has been proposed that the components be mixed in a closed receptacle with a removable closing means into which the components are successively metered in. The proposed receptacle was a transparent, flexible plastic bag initially containing the powder component to which the component in the cream form is introduced, after which the mix is prepared by kneading the flexible wall of the bag.
Once the paste mix has reached the desired consistency, it is expelled through the neck of the bag into another receptacle from which it is applied to the hair with the aid of a brush.
Hence the known device involves the use of a receptacle for making the mix and a receptacle for receiving it from the first receptacle with a view to its application.
In addition, U.S. Pat. No. 3,085,281 for example teaches bottles designed to contain products that must be shaken before use, such as nail varnish, provided on the inside with an agitator driven rotationally by an operating element located on the outside of the bottle. Known bottles provide a stirring and mixing function for products that have the consistency of a varnish but do not have the characteristics that allow a cosmetic paste to be prepared in a mixing phase during which the agitator must withstand high stresses without damage.